Life expectancy for individuals living with spinal cord injuries (SCI) has increased dramatically in the past five decades. Improvements in care and treatment of persons with SCI have resulted in these individuals living longer, more productive lives. However, inactive lifestyles and lack of physical activity following SCI result in health problems that are not related to the cause of injury but to the injury itself. These are called secondary impairments such as bone breakdown (i.e., fractures), increased risk of heart disease (heart attack and stroke), and skin breakdown (pressure sores). Currently, preventative treatment strategies are the most effective tools to actively combat these impairments.
Electrical stimulation (E-Stim) has been widely used in the prevention of secondary impairments following spinal cord injury (SCI). It was first introduced in the clinical arena in the early 1960’s by the American bioengineer, W. Liberson. The basic principal of E-Stim is to replace nerve impulses with electrical signals to the skin or muscles that become interrupted by damage to the brain, spinal cord, or peripheral nerves.
There are two common types of E-Stim used frequently in rehabilitation: Therapeutic Electrical
Neuromuscular Stimulation (TENS) and Functional Electrical Stimulation (FES). The intensity and current of E-Stim is quite different for TENS and FES and must be adjusted for each modality. TENS is used primarily to treat problems such as skin breakdown and to increase blood flow throughout the body. FES, on the other hand, is used to move a part of the body such as extending the knee, standing, or leg cycling. FES combined with exercise provide therapeutic benefits that include increasing muscle strength and endurance, improving cardiovascular fitness, decreasing the risk of heart attack and other circulation problems, as well as decreasing spasticity, swelling, muscle tightness, and the rate of osteoporosis in the stimulated extremities.
At the University of Connecticut’s Functional Performance Laboratory (Storrs Campus), groundbreaking research is being conducted that will potentially pioneer the way FES and TENS are used in the rehabilitation of SCI.
The focus of our research involves the following two major areas: 1) investigating ways to optimize the electrically induced-Leg Cycle Ergometry (LCE) to potentially allow more individuals with SCI to benefit from the FES mediated exercise system. We are looking to improve the FES-LCE and make it a more feasible and user-friendly exercise machine for use by SCI individuals; 2) investigating ways to improve circulation, prevent blood clotting in the legs, and prevent fainting following tilting and standing in individuals with SCI.
Our goal has been to use FES as a mechanical pump to move the stagnated blood in the lower limbs of SCI patients who spend long periods of time sitting in a wheelchair. This stagnant blood is the major cause for blood clotting in SCI. We are also evaluating ways to prevent pressure sores and skin breakdowns by increasing the circulation of the blood in the areas that have impaired blood circulation (i.e., sitting areas).
Although current biomedical research is rigorously searching for a cure, it is important to not overlook the importance of therapeutic strategies that provide treatment and health maintenance for today’s SCI population. Understanding the possible preventative as well as ameliorating effects of E-Stim on individuals with SCI are significant issues for future clinical studies. Electrical stimulation, as a medium for exercise and therapy, continues to gain positive recognition due in part to the progress made in computer engineering and hardware design which allow for stimulators to be smaller and even more effective. In fact, new surgical techniques enable the use of micro-stimulators implanted into selective muscles to stimulate nerves directly within the body using a remote box with no wire attached to the patients. This advancement of E-Stim technology will undoubtedly continue to evolve and potentially revolutionize SCI rehabilitation well into the next millennium.
For more information please call Dr. Pouran Faghri, @ (860) 486-1773 (Functional Performance Laboratory, University of Connecticut) or her office at (860) 486-0018.